On 2018-07-20 19:37, Daniel Thompson wrote:
On 09/07/18 11:22, Kiran Gunda wrote:
Handle the short circuit interrupt and check if the short circuit interrupt is valid. Re-enable the module to check if it goes away. Disable the module altogether if the short circuit event persists.
Signed-off-by: Kiran Gunda kgunda@codeaurora.org Reviewed-by: Bjorn Andersson bjorn.andersson@linaro.org
Changes from V3:
- Added Reviewed by tag.
- Addressed minor comments from Vinod
drivers/video/backlight/qcom-wled.c | 132 ++++++++++++++++++++++++++++++++++-- 1 file changed, 128 insertions(+), 4 deletions(-)
diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c index 362d254..a14f1a6 100644 --- a/drivers/video/backlight/qcom-wled.c +++ b/drivers/video/backlight/qcom-wled.c @@ -10,6 +10,9 @@
- GNU General Public License for more details.
*/ +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/ktime.h> #include <linux/kernel.h> #include <linux/backlight.h> #include <linux/module.h> @@ -64,6 +67,16 @@ #define WLED3_SINK_REG_STR_CABC(n) (0x66 + (n * 0x10)) #define WLED3_SINK_REG_STR_CABC_MASK BIT(7) +/* WLED4 specific control registers */ +#define WLED4_CTRL_REG_SHORT_PROTECT 0x5e +#define WLED4_CTRL_REG_SHORT_EN_MASK BIT(7)
+#define WLED4_CTRL_REG_SEC_ACCESS 0xd0 +#define WLED4_CTRL_REG_SEC_UNLOCK 0xa5
+#define WLED4_CTRL_REG_TEST1 0xe2 +#define WLED4_CTRL_REG_TEST1_EXT_FET_DTEST2 0x09
- /* WLED4 specific sink registers */ #define WLED4_SINK_REG_CURR_SINK 0x46 #define WLED4_SINK_REG_CURR_SINK_MASK GENMASK(7, 4)
@@ -113,17 +126,23 @@ struct wled_config { bool cs_out_en; bool ext_gen; bool cabc;
- bool external_pfet; }; struct wled { const char *name; struct device *dev; struct regmap *regmap;
- struct mutex lock; /* Lock to avoid race from thread irq handler */
- ktime_t last_short_event; u16 ctrl_addr; u16 sink_addr; u16 max_string_count; u32 brightness; u32 max_brightness;
- u32 short_count;
- bool disabled_by_short;
- bool has_short_detect; struct wled_config cfg; int (*wled_set_brightness)(struct wled *wled, u16 brightness);
@@ -174,6 +193,9 @@ static int wled_module_enable(struct wled *wled, int val) { int rc;
- if (wled->disabled_by_short)
return -EFAULT;EFAULT means bad address (memory fault). Perhaps EIO or maybe even something more exotic like ENXIO might be more appropriate?
- rc = regmap_update_bits(wled->regmap, wled->ctrl_addr + WLED_CTRL_REG_MOD_EN, WLED_CTRL_REG_MOD_EN_MASK,
@@ -210,18 +232,19 @@ static int wled_update_status(struct backlight_device *bl) bl->props.state & BL_CORE_FBBLANK) brightness = 0;
- mutex_lock(&wled->lock);
if (brightness) { rc = wled->wled_set_brightness(wled, brightness); if (rc < 0) { dev_err(wled->dev, "wled failed to set brightness rc:%d\n", rc);
return rc;
goto unlock_mutex;
return rc;
goto unlock_mutex;backlight_device *bl) rc = wled_module_enable(wled, !!brightness); if (rc < 0) { dev_err(wled->dev, "wled enable failed rc:%d\n", rc);
return rc;
goto unlock_mutex;- mutex_unlock(&wled->lock);
- return rc; } +#define WLED_SHORT_DLY_MS 20
+#define WLED_SHORT_CNT_MAX 5 +#define WLED_SHORT_RESET_CNT_DLY_US USEC_PER_SEC
+static irqreturn_t wled_short_irq_handler(int irq, void *_wled) +{
- struct wled *wled = _wled;
- int rc;
- s64 elapsed_time;
- wled->short_count++;
- mutex_lock(&wled->lock);
- rc = wled_module_enable(wled, false);
- if (rc < 0) {
dev_err(wled->dev, "wled disable failed rc:%d\n", rc);goto unlock_mutex;- }
- elapsed_time = ktime_us_delta(ktime_get(),
wled->last_short_event);- if (elapsed_time > WLED_SHORT_RESET_CNT_DLY_US)
wled->short_count = 0;Shouldn't this reset to 1 (e.g. we have just seen a short).
Daniel.
Ok. I will change it in the next series.